CVE-2026-12302
Medium
Description
Mitigation bypass in the DOM: Security component. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, Firefox ESR 115.37, Thunderbird 152, and Thunderbird 140.12.
SeverityMedium
CVSS6.5
Exploit probability—
Product
Mozilla Firefox
PublishedJun 16, 2026
First seenJun 16, 2026
Weakness typeCWE-693CWE-693
How to fix
Update
- mozilla firefox140.12.0, 152.0.0 or later
- mozilla thunderbird140.12.0, 152.0.0 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| mozilla firefox | v < 140.12.0, v < 152.0.0 | 140.12.0, 152.0.0 |
| mozilla thunderbird | v < 140.12.0, v < 152.0.0 | 140.12.0, 152.0.0 |
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